In which configuration setting is the number of replicas for the deployed service defined?

The number of replicas for the deployed service is usually specified in the configuration of the container orchestrator or deployment management system. For example, in Kubernetes, it is specified in the replicas field in a Deployment object:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: example-deployment
spec:
  replicas: 3  # The number of replicas is set here
  selector:
    matchLabels:
      app: example
  template:
    metadata:
      labels:
        app: example
    spec:
      containers:
      - name: example-container
        image: example-image

In other systems, such as Docker Swarm, the number of replicas is specified in the service parameters during its creation or update.